Device and method for constrained wave-field separation

Abstract

Computing device, computer instructions and method for up-down separation of seismic data. The method includes receiving the seismic data, which includes hydrophone data and particle motion data; performing a first up-down separation, which is independent of a ghost model, using as input the hydrophone data and the particle motion data, to obtain first up-down separated data; performing a second up-down separation by using as input a combination of (i) the hydrophone data and/or the particle motion data and (ii) the first up-down separated data, wherein an output of the second up-down separation is second up-down separated data; and generating an image of the subsurface based on the second up-down separated data.

What is claimed is: 
     
       1. A method performing up-down separations of seismic data, the method comprising:
 receiving the seismic data, which includes hydrophone data and particle motion data; 
 performing a first up-down separation, which is independent of a ghost model, using as input the hydrophone data and the particle motion data, to obtain first up-down separated data; 
 performing a second up-down separation by using as input a combination of (i) the hydrophone data and/or the particle motion data and (ii) the first up-down separated data, the second up-down separation outputting second up-down separated data; and 
 generating an image of the subsurface based on the second up-down separated data. 
 
     
     
       2. The method of  claim 1 , wherein the input for the second up-down separation includes (1) only the hydrophone data and (2) the first up-down separated data. 
     
     
       3. The method of  claim 1 , wherein the input for the second up-down separation includes (1) only the particle motion data and (2) the first up-down separated data. 
     
     
       4. The method of  claim 1 , wherein the input for the second up-down separation includes (1) the hydrophone data, (2) the particle motion data and (3) the first up-down separated data. 
     
     
       5. The method of  claim 1 , wherein the second up-down separation is a ghost model-dependent process. 
     
     
       6. The method of  claim 1 , wherein the first up-down separated data is a summation of the hydrophone data and the particle motion data. 
     
     
       7. The method of  claim 6 , wherein the particle motion data is corrected for obliquity prior to the first up-down separation. 
     
     
       8. The method of  claim 1 , wherein the particle motion data is processed to reduce a noise content prior to the first up-down separation. 
     
     
       9. The method of  claim 1 , wherein the first up-down separated data is a difference between the hydrophone data and the particle motion data. 
     
     
       10. The method of  claim 1 , wherein the second up-down separation is an inversion process that calculates a wave-field separated model p based on the seismic data and a matrix L, which depends on time delays associated with up-going wave-fields and down-going wave-fields. 
     
     
       11. A computing device performing up-down separations of seismic data, the computing device comprising:
 an interface configured to receive the seismic data, which includes hydrophone data and particle motion data; and 
 a processor connected to the interface, the processor configured to, 
 perform a first up-down separation, which is independent of a ghost model, using as input the hydrophone data and the particle motion data, to obtain first up-down separated data, 
 perform a second up-down separation by using as input a combination of (i) the hydrophone data and/or the particle motion data and (ii) the first up-down separated data, the second up-down separation yielding second up-down separated data, and 
 generate an image of the subsurface based on the second up-down separated data. 
 
     
     
       12. The computing device of  claim 11 , wherein the input for the second up-down separation includes (1) only the hydrophone data and (2) the first up-down separated data. 
     
     
       13. The computing device of  claim 11 , wherein the input for the second up-down separation includes (1) only the particle motion data and (2) the first up-down separated data. 
     
     
       14. The computing device of  claim 11 , wherein the input for the second up-down separation includes (1) the hydrophone data, (2) the particle motion data and (3) the first up-down separated data. 
     
     
       15. The computing device of  claim 11 , wherein the second up-down separation is a ghost model-dependent process. 
     
     
       16. The computing device of  claim 11 , wherein the first up-down separated data is a summation of the hydrophone data and the particle motion data. 
     
     
       17. The computing device of  claim 11 , wherein the particle motion data is processed to reduce a noise content prior to the first up-down separation. 
     
     
       18. The computing device of  claim 11 , wherein the first up-down separated data is a difference between the hydrophone data and the particle motion data. 
     
     
       19. The computing device of  claim 11 , wherein the second up-down separation is an inversion process that calculates a wave-field separated model p based on the seismic data and a matrix L, which depends on time delays associated with up-going wave-fields and down-going wave-fields. 
     
     
       20. A non-transitory computer readable medium including computer executable instructions, wherein the instructions, when executed by a processor, implement instructions for performing up-down separations of seismic data, the instructions executing a method comprising:
 receiving the seismic data, which includes hydrophone data and particle motion data; 
 performing a first up-down separation, which is independent of a ghost model, using as input the hydrophone data and the particle motion data, to obtain first up-down separated data; 
 performing a second up-down separation by using as input a combination of (i) the hydrophone data and/or the particle motion data and (ii) the first up-down separated data, the second up-down separation outputting second up-down separated data; and 
 generating an image of the subsurface based on the second up-down separated data.